Circuit closer



AVAILABLE CCJPY March 30 1926. 1,578,563

7 J. w. THOMAS CIRCUIT CLOSER Filed Jan. 19, 1921 M a btommgs ing the feeding Patented Mar. 30, 1 926.

UNlTED srn ras JOHN W. THOMAS, 0E FULLERTON, PENNSYLVANIA, ASSIGNORTO FULLER-LEHIGH COMPANY, A CORPORATION OF PENNSYLVANIA.

CIRCUIT CLOSER.

Application filed January 19, 1921. Serial No. 438,516.

To all whom it may concern:

Be it known that I, J OHN W. THoMAs, a citizen of the United States, residing at Ful lerton, in the county of Lehigh, State of Pennsylvania, have invented certain new and useful Improvements in Circuit Closers; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which 't appertains to make and use the same.

The present invention relates to circuit closing devices adapted for use in conjunction with containers, more especially a tank or bin for liquids or finely divided solids such as pulverized coal, to control the filling of the container and to indicate as well when the bin is empty, as the intermediate progressive levels of the material during the filling and emptying of the bin.

The invention comprehends as one of its parts the combination with a bin provided with means for feeding material thereto, of a device responsive to the pressure of the material in the bin for controlling the feeding means. the bin reaches a, predetermined height fixed by the position of the device in the bin, which would ordinarily be close to the top opening thereof, the pressure of the material on its parts to automatically shut off the feeding of material, thus precludingthe overflow of the bin. This might easily occur where for instance a signalling device which is depended upon to give warning to an operator to shut off the material when the bin is full, is unheeded. The means for feeding material to the bin may consist of power operated mechamsm, preferably motor driven, in which case the device responds to the pressure of the material in the bin to start and stop the feeding mechanism, as by starting and stopping the motor. Irrespective of the means for drivmechanism, but preferably in accordance with an arrangement whereby a motor is employed for this purpose, such mechanism embodies a hopper and a; screw conveyor. In the specific embodiment of the invention hereinafter described the motor for driving the screw conveyor is in circuit with an overload circuit breaker and the controlling device, located nearthe'upper,

end 'of the bin, operates the circuit breaker When the material being fed to the device operates through a p to stop the motor and the feeding of mateby the screw conveyor'when the bin is For whatever purpose the device may be used, as, for instance, to shut olf the means for feeding material to a bin when the bin is full, or for the purpose of indicating the progressive heights reached by the material during the filling and emptying of the bin, the device comprises a pair of diaphragms, preferably flexible, which are both exposed to the same pressure, the variations in which, from a selected normal, cause the device to operate. Associated with the device may be an electric circuit which is;control1ed by the movements of the diaphragms, and the device may embody circuit-controlling means which are operated by thediaphragms to open the circuit when the diaphragms are subjected to a pressurein excess of the se lected normal. In any event, however, the

diaphragms are caused to have a relative movement, due to variations in pressure from the selected normal, and the circuitcontrolling means, which may conveniently take the form of a pair of contacts, one associated with each of the diaphragms, may also be arranged to be given a relative movement, upon the relative movement of the diahragms. Each diaphragm is preferably provided at its center with a'stiffening member which serves to reinforce and protect the diaphragm and also to provide a means by which the circuit controller may be actuated. In one form of the device I make use of .a pair ofdiaphragms which are mounted on opposite sidesfof a housing in the form of a ring which is intended to be placed within the bin or other container so that both diaphragms are exposed to the pressure of the material within the bin. In

the space between the diaphragms is a cu These flexible arms are connected intermediatetheir ends with the stiffening members, and asithe diaphragms move the arms are caused to flex so as to produce a relative movement of the contact members either of separation or approach. In the preferred struction described hereinafter also includembodiment of the invention I make use of a pair of flexible diaphragms and a pair of flexible arms, each of which carries a. con tact. These arms are so arranged that as the diaphragms are moved toward each other by pressure variations in excess of the selected value, the contact members are caused to separate. These contacts in turn form part of an electric circuit which is arranged with suitableindicating and other devices so that a signal may be given, or, if desired, a piece of machinery, as, for instance, the motor associated with the feeding mechanism, may be shut off. The diaphragms are mounted in spaced relation in the housing, and the contact members on their arms are placed between them. Both diaphra'gms are thus exposed to the pressure, the variations in which cause the device to operate, and both contact members are given a simu1taneous movement as the diaphragms are moved.

In another form of the device I make use of a single diaphragm exposed to the pressure. This diaphragm is provided with a stiffener, and the flexible arm having one free end on which is mounted a contact, is secured to the stiffener intermediate its ends. A second cont-act member adapted to cooperate with the first is supported within the housing on which the diaphragm is mounted, and as the diaphragm is moved by pressure variations, the contacts are caused to move relatively to each other so as to open or close a circuit, as the case may be.

The device is capable for use in indicating the progressive heights which are reached by the material as the bin is being filled, as, for instance, by causing the contact members to control a circuit which lights a lamp when the pressure of the material on the diaphagms causes the contacts either to separate or come together, but the device is also capableof use for indicating when the bin is empty. In this adaptation of the invention the diaphragm or diaphragms may be arranged so that upon the release of pres sure caused by the level of the material falling below that at which the device is located the contact members will either move together or apart in such a way as to establish or break a circuit which may, in turn,

operate a signal or some other piece paratus.

The different parts of the present invention described in the foregoing may be variously employed conjunctively to produce for example, the combination with a bin provided with means for feeding material thereto, of a device responsive to the pressure of the material in the bin for controlling said feeding means, and means for indicating the progressive filling and emptying of the bin; or as in the preferred conof aping means for indicating when the bin is empty.

In the drawings, Fig. 1 is a View of a pressure responsive element provided with two diaphragms; Fig. 2 is a modified pres,- sure responsive element provided with one diaphragm; and Fig. 3 shows a modified mounting for one of the pressure responsive elements.

the carbon contact pieces 9. One of these spring arms 0 is made in two parts, the two ends being insulatedfrom each other by the insulating block 10, in which its ends are mounted. The stiffening discs 4 are an important adjunct of the invention. They serve to both mount the resilient arms 5 in operative relation with the diaphragms and to prevent the carbon contact pieces and associated parts from contacting with and puncturing the adjacent diaphragm, when the diaphragms are pressed toward one an'- other. The current is led to the contact blocks 9 through the wires 12.

The pressure responsive element is placed on the inside of the bin, so that the mate rial in the bin will press against both diaphragms. A bracket for so mounting it may be attached to the lower part of the ring 1 as indicated at 13. It is evident that pressure of the material in the bin will cause the circuit \to be broken, which operation will operate a suitable signal as will be de scribed.

tcferring now to Fig. 2, a modification is shown in which but a single diaphragm, indicated at 14, is used. This diaphragm is mounted upona suitable casing 15, which is flanged as indicated at 16, for mounting in a suitable aperture in the bin 17. @therwiSe the structure and operation of this modification are very similar to that of Fig. 1, the corresponding parts being similarly numbered. v

Referring now to Fig. 3, the bin 17 is shown as filled with liquid or finely divided solid, such as pulverized coal, for example, to the height indicated at 18. A plurality of pressure responsive devices, of the kind shown in Fig. 1, are mounted at various levels in the bin 17, such devices being indicated generally at 19 and 20. Each of these pressure responsive devices controls an electric. circuit 22 in which signals, such as the lamps 23, are located. It will be apparent that when the material in the bins is in contact with one of these indicators 19 or 20 the lamps will be dark, and that when the material falls below these devices 'the'lamps will be lighted. The lighting and 'egttinguishing of these lamps will therefore give both an indication of the level of the material in-the bin as well as an indication of the rate at which it is being filled or emptied. I

I At the bottom ofthe bin is located a signal for indicating when the bin is empty. 1n its preferred form'this device comprises a. pressure responsive circuit closing device 24, comprising spring arms designed to be brought intocontact by pressure of the material in the bin against them. This device is in circuit with a relay 25, the relay in turn controlling both the bell 26 and the lamps 27. When the materialin the bin falls below the pressure responsive device 24, the circuit is broken and the bell 26 and the lamps 27 will be operated to give an alarm that the bin is empty. The lamps 27 are normally extinguished.

Near the top of the bin is located a pressure responsive device 28 similar to 19 and 20, this device, however, controlling a. relay 29 as well as the usual signalling lamps 23. The relay 29 controls an audible signal such as. the bell 30. It will be apparent that when the material in the bin reaches the level of "the element 28 the circuit will be broken by 28, whereupon the relay 29 will close the circuit to the bell 30 to give an alarm that the bin is filled.

At the top of the bin is a pressure respon sive element 32, similar to 19 and 20, thisv clement controlling the circuit 33, in which is located the overload circuit breaker. 34. This circuit breaker controls the circuit 35 through the motor 36, which operates any desired form of mechanism for feeding material to the bin, here shown as a screw conveyor 37. \Vhen the material reaches the level of the pressure responsive device 32, the motor 36 will be disconnected so as to stop further fillingyof the bin. I

\Vhen the bin is nearly empty the lights 27 will be lighted and the bell 26 will be rung to indicate that fact. As the bin fills, these signals will be disconnected and the lights 23, placed at various levels, will be successively extinguished as the material in the binfattains successive levels. When the material in the bin reaches the level of the pressure responsive element 28 an alarm bell 30 will be rung. Anyoverflow of the bin is prevented by the pressure responsive. device 32 which throws out the filling mechanism 36 and 37. when the material in the bin reaches the top.

he modification shown in Fig. 3 shows the contact carbons 9 and their associated arms mounted in a detachable glass casing,

placed between which projects outside of the bin, so that the parts may be readily repaired and in spected. The glass casing indicated at 40 is carried by the mounting ring 41 held in a suitable aperture in the wall of the bin 17. A pressure responsive diaphragm 14 is mounted in the inner side of the mounting 41. so as to be subjected to pressure of the liquid or fine'ly divided solid in the bin.

I claim:

1. A circuit closer actuated by variations in pressure comprising't-he combination of a pair of diaphragms placed face to face and exposed to the same actuating pressure these diaphragms being arranged to be given a simultaneous relative movement by variations in the pressure from a selected value, and a contact member associated with each diaphragm and movable thereby, these contact members being disposed between the diaphragms and being arranged to cooperate and to be given a relative movement of separation when the diaphragms are subjected to a pressure in excess of the normal value.

iii-pressure com rising the combination of a pair of flexible diaphragms directly exposed to the same actuating pressure, each of these diaphragms being movable toward the other when the pressure exceeds a selected value, and a contact member associated with each 2. A circuit closer actuated by variations diaphragm, these contact members being the diaphragms and being arranged to cooperate and to be moved apart when the diaphragms move toward each other.

3. In a circuit closer actuated by variatlons n pressure, the combination of a flexible diaphragm exposed to the pressure and provided with aj stifi'ener, a resilient arm anchored at one end and carrying a contact member on its free end, the said arm being secured to the stiffener intermediate its ends and being adapted to beflexed by the diaphragm as the latter is moved by pressure variations, and' a second contact member arranged to cooperate with the first.

4. A circuit closer actuated by variations inpressure comprising the combination of a housing, a pairof flexible diaphragms se-' cured to the housing and adapted to be exposed to the actuating pressure, these diaphragms being relatively movable accordin to pressure variations, a stiffener on cam diaphragm, a pair of resilient arms, each arm being associated with a diaphragm and secured at one end to the housing, each arm being secured intermediate its ends to one of the stitfeners, and contact members mounted on the free ends of the arms and arranged to cooperate.

5. A circuit closer actuated by variations in pressure comprising the combination of a pair of diaphragms exposcd'to the actuatmesses ing pressure and movable toward! each other the arms, the arms and contact members when the pressure exceeds a selected value, being so arranged as to cause the contact stiffeners on the diaphragms, an arm assomembers to be separated when the dia- 10 ciated with each diaphragm, this arm being phragms are moved toward each other by 5 anchored at one end and being secured to pressure in excess of the selected value.

the stifl'ener intermediate its ends, and con- In testimony whereof I affix my signature. tact members carried on the free ends of JOHN W. THOMAS. 

